JPH04210741A - Power supply change-over device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power switching device. [0002]

2. Description of the Related Art In recent years, cogeneration power generation devices have been developed that have higher energy recovery efficiency than conventional power generation devices. [0003] Cozy energy generates electricity by driving a generator using an engine, gas turbine, etc., and at the same time recovers heat from the exhaust gas, casing, etc. generated by the engine, gas turbine, etc. through heat exchange. This type of cogeneration system is generally small in size, making it suitable for use as private power generation equipment. [0004] Hereinafter, a power supply switching device when cogeneration is used as private power generation equipment will be described using FIG. 3. [0005] Note that the private power generation equipment may be other than cogeneration, so hereinafter it will simply be referred to as a power generation device.

In the figure, 1 is a commercial power source, and 2 is a power generation device such as the above-mentioned cogeneration system. 3 is various lighting equipment 4゜5
, 6. This is a switching device that selectively switches between the commercial power source 1 and the power generation device 2 with respect to 7. [0007] 9 is an electromagnetic contactor provided inside the switching device 3 for turning on the commercial power supply 1, 10 is an electromagnetic contactor for turning on the generator 2, and 11 is an instrument for detecting the current value of the generator 2. Current transformer (CT), 12 is instrument current transformer (CT)
Based on the detection signal 13 from 11, the electromagnetic contactors 9 and 1
This is a control device that sends a switching command 14.15 to 0. [0008] Then, the switching device 3 is switched to the power generation device 2 side, and the lighting equipment 4. 5. 6. 7 is turned on by the power from the power generator 2, if an overload is applied to the power generator 2, the control device 12 detects the occurrence of overload by the detection signal 13 from the voltage transformer (CT) 11. Upon detection, a switching command 14 is sent to the electromagnetic contactor 9 for turning on the commercial power supply 1 to turn on the electromagnetic contactor 9, and at the same time, a switching command 15 is sent to the electromagnetic contactor 10 for turning on the power generator 2 to turn on the electromagnetic contactor. 10, the switching device 3 is switched to the commercial power supply 1 side, and the lighting equipment 4. 5. 6. 7 is turned on by the current from the commercial power supply 1. [0009] When the switching device 3 switches to the commercial power supply 1 side and the overload state of the power generation device 2 is released, the control device 12 detects the overload by the detection signal 13 from the instrument current transformer (CT) 11. Upon detecting the release of the state, a switching command 14 is sent to the electromagnetic contactor 9 for turning on the commercial power supply 1 to turn off the electromagnetic contactor 9, and at the same time, the electromagnetic contactor 10 for turning on the power generator 2 is sent.
By sending a switching command 15 to turn on the electromagnetic contactor 10, the switching device 3 is switched to the power generation device 2 side, and the lighting equipment 4. 5. 6. 7 is again turned on by the power from the power generator 2.

0OIO] The power generation device 2 such as cogeneration,
Conventional lighting equipment with low load 4. 5. 6. 7, so even if it is designed to switch all at once to the commercial power supply 1 side when an overload occurs on the generator 2, in reality, the commercial power supply 1 side is frequently used. Since there is almost no fear that the power generation device 2 will switch to the power generation system, the power generation device 2, such as a cogeneration system with high energy recovery efficiency, can be stably used. [00111

[Problem to be solved by the invention] However, in recent years, there has been a desire to widely utilize power generation devices 2 such as cogeneration systems with high energy recovery efficiency in other fields, and for example, automatic start/stop equipment, etc., has a large load. It is desired to drive equipment that requires a large starting current, but
When attempting to operate equipment such as automatic start/stop equipment,
Due to repeated starting and stopping of automatic starting/stopping equipment, the power generator 2 can easily become overloaded, and therefore the commercial power supply 1 is frequently overloaded.
There is a problem that the usage rate of the power generation device 2 such as a cogeneration system with high energy recovery efficiency is reduced due to switching to the side, and the power generation device 2 is instantaneously switched to the There is a problem in that a voltage drop occurs in the power generator 2, and other devices connected to the power generation device 2, such as automatic start/stop devices, are adversely affected. [00121] In view of the above-mentioned circumstances, the present invention provides a power supply switching device that makes it possible to effectively use a power generation device such as a cogeneration system with high energy recovery efficiency when driving equipment such as automatic start/stop equipment. The purpose is to provide the following. [0013] [Means for Solving the Problems] The present invention provides a switching board capable of switching between a commercial power source and a power generation device to supply current to equipment;
A start detection panel detects the start and stop of the equipment and outputs a detection signal, and based on the detection signal from the start detection board, switches to the commercial power source when the equipment starts and stops, and switches to the generator side when the equipment is operating. The present invention relates to a power switching device characterized by comprising a control device that sends a switching command to a switching panel to perform switching. [0014]

[Operation] According to the present invention, the start detection panel detects the start and stop of the equipment and outputs a detection signal to the control device, and the control device sends a switching command to the switching board based on the detection signal to start the equipment. Switch to the commercial power supply side when the power is off and after stopping, and switch to the power generator side when the equipment is operating. [0015]

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the drawings. [0016] FIGS. 1 and 2 show an embodiment of the present invention. [00171 In the figure, 16 is a commercial power source, 17 is a drive source 18 such as an engine or gas turbine, a generator 19, and a heat exchanger 20.
This is a power generation device such as a cogeneration system consisting of a circuit breaker panel 19 and a circuit breaker panel 19. [0018] On the other hand, 21, 22, 23.24 are devices such as automatic start/stop devices such as refrigerators and compressors;
25.26, 27.28 are (automatic start/stop) equipment 21, 22
．． It is a starting device such as automatic start/stop device of 23.24. [0019] 29, 30, 31.32 is commercial power supply 16
This is a switching board equipped with an electromagnetic contactor 33 for inputting and an electromagnetic contactor 34 for inputting the power generator 17. [0020135, 36, 37, 38 are switch boards 29, 3
A starting detection panel connected between 0.31.32 and the devices 21, 22, 23.24, and 39 a starting detection panel 35.
．． 36, 37, and 38 are power supply circuit breakers such as fuses installed in the middle of the power supply line 75; 40 is a current transformer (CT) installed downstream of the power supply circuit breaker 39; and 41 is a voltage transformer. Starting signals 42. from the starting devices 25, 26, 27, 28 provided downstream of the CT 40. It is a two-contact electromagnetic contactor that turns on at 43°44.45. [00211 Also, 46 is each start detection panel 35, 36, 37
．． Detection signal 47 from 38 instrument current transformer (CT) 40
, 48.49. 50, and starting detection signals 51.51', 52.52' from the two-contact type electromagnetic contactor 41,
53.53', 54.54', and the priority setting signal 56 from the device priority setting device 55,
Magnetic contactor 33.3 of each switching panel 29, 30, 31.32
Switching command to 4 57. 58. 59. 60. 61.
62. 63. It is a control device that sends 64. [0022] 65.6'6, 67.68 are start detection signals 51.51', 52 from the two-contact type electromagnetic contactor 41.
．． 52', 53.53', 54.54' and outputs a delay signal 69.70.71.72. 37, 38 etc. may be provided. [00231 Next, the operation will be explained. [0024] The point that each device 21, 22, 23, 24 is switched to the commercial power source 16 or the power generator 17 and driven is the same as in FIG. [0025] When starting the devices 21, 22, 23.24, the starting devices 25, 2 of the devices 21, 22, 23.24
From 6.27.28, the starting signals 42, 43, 44.45 are sent to the two-contact electromagnetic contactor 41 of the corresponding starting detection board 35, 36, 37.38, and the two-contact electromagnetic contactor 41
is turned on. Then, starting detection signals 51.51', 52.5 are sent from the two-contact type electromagnetic contactor 41 to the control device 46.
2', 53.53', 54.54' are sent, and the start detection signals 51.51', 52.52", 53.53', 5
4.54', the control device 46 switches the switching board 29. 30.
At the same time, the switching commands 57, 58, 59.60 are sent to the switching boards 29, 30, 59.60 to turn on the electromagnetic contactor 33 for turning on the commercial power supply 16, and the switching commands 61 are sent to the switching panels 29, 30, 31.32.
, 62, 63, and 64 to turn off the electromagnetic contactor 34 for turning on the power generator 17. As a result, the switching board 29.
30°31.32 is switched to the commercial power supply 16 side and the equipment 21
, 22, 23, and 24 are started by the commercial power supply 16. [0026] Starting detection signals 51.51', 52.52', 53.53 from the two-contact type electromagnetic contactor 41
' , 54.54' is the timer 65. 66, 67,
68, and after a certain period of time has elapsed, a delayed signal 69. 7
0. 71.72 is output. When the delay signal 69°70.71.72 is generated, the control device 46 outputs the detection signal 47.48.49.50 from the current transformer (CT) 40 of the start detection panel 35, 36.37.38. is the equipment 21. 2
2. Equipment 21, 22, 23 that has been confirmed to be stable by confirming that the starting current value has reached a normal value below the starting current value of 23゜24.
．． 24 is determined to be in a state where switching to the power generation device 17 is possible. [0027] Then, in accordance with the priority setting signal 56 from the equipment priority setting device 55, the control device 46 selects the devices 21, 2 of the maximum number of devices in which the power generation device 17 does not exceed the rated output.
Switching board 29 corresponding to 2.23.24. 30. 31
．． 32 to turn off the electromagnetic contactor 33 for turning on the commercial power supply 16, and at the same time send switching commands 61, 62, 63.64 to the generator 1.
7. Turn on the electromagnetic contactor 34 for charging. This results in
For example, set the priority order of devices 21, 22, 23, and 24 to device 21 first, device 22 second, device 23 third, and device 2.
4 is No. 4, and assuming that the maximum number of devices in which the power generation device 17 does not exceed the rated output is three, then device 21. 2
2. 23 is driven by the power generation device 17, and the equipment 24 is driven by the commercial power source 16, so that the power generation device 17 is used near its rated output. [0028] In this way, each device 21. 22. 23
．． 24 is started by the commercial power supply 16, and the required number of devices 21, 22, 23 are immediately switched to be driven by the generator 17, so that the instantaneous starting current of the devices 21, 22, 23, 24 causes the generator to This prevents a voltage drop from occurring in the power generator 17 and adversely affecting other equipment connected to the power generator 17. [0029] Next, when any of the devices 21.22.23 driven by the power generating device 17 is stopped, the starting signal 42.43.44 from the starting device 25.26.27 disappears, so the corresponding Magnetic contactor 41 is turned off. As a result, starting detection signals 51, 51', 52, 52°
, 53, 53° are eliminated and the current transformer (CT) 4
Since the detection signals 47, 48, 49 of 0 become the value O, the starting detection signals 51, 51', 52, 52', 53° 53' or the detection signals 47, 48, . 49
If one of the two changes as described above, the control device 4
6 is the switching panel 29.30 for the corresponding equipment 21, 22.23
．． 31 to switch commands 57, 58, and 59 to commercial power supply 1.
At the same time, the switching commands 61, 62, and 63 are sent to turn off the electromagnetic contactor 34 for turning on the generator 17, and instead, the switching commands 61, 62, and 63 are sent to turn off the electromagnetic contactor 34 for turning on the power generator 17, and instead, the switching commands 61, 62, and 63 are sent to turn off the electromagnetic contactor 34 for turning on the power generator 17. A switching command 60 is sent to the switching board 32 of the equipment 24 in the next order to turn off the electromagnetic contactor 33 for turning on the commercial power supply 16, and at the same time, a switching command 64 is sent to turn off the electromagnetic contactor 34 for turning on the power generator 17. turn on. As a result, the stopped devices 21, 22, and 23 are switched to the commercial power source 16, and the device 24 that was waiting on the commercial power source 16 side is transferred to the power generator 17 side. Therefore, since the power generation device 17 is always used near the rated output, the power generation device 17 can be used effectively and overload of the power generation device 17 can be prevented. Thereafter, the same operation as described above is repeated every time the devices 21, 22, 23, 24 driven by the power generator 17 are started or stopped. [00301 In addition, when an overload occurs in the power generation device 17, the detection signals 47, 48 of the current transformer (CT) 40
．． Since 49.50 is an abnormal value, the control device 46 detects this and switches all the switching panels 29, 30, 31.32 to the commercial power supply 16 side. [0031] Furthermore, when the power generation device 17 has a power outage,
Detection signal 47 of instrument current transformer (CT) 40. 48.4
Since the value of 9.50 becomes O, the control device 46 detects this and switches all the switching panels 29, 30, 31.32 to the commercial power supply 16 side. [0032] The above is summarized in the control flowchart of FIG. [0033] The present invention is not limited to the above-described embodiments, but can be widely applied to devices other than automatic start/stop devices, and other aspects do not depart from the gist of the present invention. Of course, various changes can be made therein. [0034]

As explained above, according to the power supply switching device of the present invention, it is possible to prevent an overload from occurring in the power generating device, and also to prevent a voltage drop from occurring in the power generating device due to the starting current. Therefore, an excellent effect can be achieved in that the power generation device can be utilized effectively.

[Brief explanation of the drawing]

FIG. 1 is an overall system diagram of an embodiment of the present invention.

FIG. 2 is a control flowchart of the control device in FIG. 1;

FIG. 3 is an overall system diagram of a conventional example.

[Explanation of symbols]

16 Commercial power source 17 Power generator 21, 22. 23. 24 Equipment 29, 30
．． 31. 32 Switching board 35, 36. 37.
38 Start detection panel 46 Control device 47.48, 49, 50, 51, 51°, 52, 52°
, 53.53', 54.54' detection signal 57,
58. 59. 60. 61. 62. 63.
64 switching command

[Figure 1]

Claims (1)

[Claims] Claim 1: A switching board that can switch between a commercial power source and a power generator to supply current to equipment, a start detection board that detects the start and stop of the equipment and outputs a detection signal, and detection from the start detection board. A power switching device characterized by comprising: a control device that sends a switching command to a switching panel to switch to a commercial power source when starting and stopping equipment based on a signal, and to switch to a generator side when operating equipment.